Sql 连接两个表

嗨，我有两个sql查询

问题1：

Select Year, country, state, city, sales from db.sales1 (for current Year)

问题2：

Select Year, country, state, city, sales from db.sales2(For last 4 years)

要求： 从以上两个查询中选择当前年份、国家、城市、当前销售额、2015年销售额、2016年销售额

我该怎么做

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谢谢

您正在寻找

UNION ALL

Select Year, country, state, city, sales from db.sales1 
UNION ALL
Select Year, country, state, city, sales from db.sales2

或者如果你想要一份更简洁的报告

SELECT country, state, city,
       SUM( CASE WHEN Year = 2015 THEN Sales ELSE 0 END) as Sales_yr2015,
       SUM( CASE WHEN Year = 2016 THEN Sales ELSE 0 END) as Sales_yr2016
FROM (
        Select Year, country, state, city, sales from db.sales1 
        UNION ALL
        Select Year, country, state, city, sales from db.sales2
    ) T
GROUP BY country, state, city

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无意冒犯，但是你在发布这个问题之前试过谷歌或bing吗？我试过，但没发现当OP显然什么都没试过的时候，你很乐意付出一切：）